package com.heima.kafka.sample;

import org.apache.kafka.clients.consumer.*;

import java.time.Duration;
import java.util.Collections;
import java.util.Properties;

/**
 * 消费者
 */
public class ConsumerQuickStart {

    public static void main(String[] args) {
        //1.添加kafka的配置信息
        Properties properties = new Properties();
        //kafka的连接地址
        properties.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, "192.168.200.130:9092");
        //消费者组
        properties.put(ConsumerConfig.GROUP_ID_CONFIG, "group2");
        //设置手动提交
        properties.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, "false");
        //消息的反序列化器
        properties.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");
        properties.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");

        //2.消费者对象
        KafkaConsumer<String, String> consumer = new KafkaConsumer<String, String>(properties);

        //3.订阅主题
        consumer.subscribe(Collections.singletonList("itheima-topic-out"));

        //当前线程一直处于监听状态
        try {
            while (true) {
                //4.获取消息
                ConsumerRecords<String, String> consumerRecords = consumer.poll(Duration.ofMillis(1000));
                for (ConsumerRecord<String, String> consumerRecord : consumerRecords) {
                    System.out.println(consumerRecord.key());
                    System.out.println(consumerRecord.value());
                    System.out.println(consumerRecord.offset());
                    System.out.println(consumerRecord.partition());

                    //同步提交偏移量
                  /*  try {
                        consumer.commitSync();
                    } catch (Exception e) {
                        e.printStackTrace();
                    }*/

                    //异步提交偏移量
                   /* consumer.commitAsync(new OffsetCommitCallback() {
                        @Override
                        public void onComplete(Map<TopicPartition, OffsetAndMetadata> map, Exception e) {
                            if(e!=null){
                                System.out.println("记录错误的提交偏移量："+map+",异常信息为："+e);
                            }
                        }
                    });*/

                    //同步和异步提交偏移量
                    //异步提交偏移量
                    consumer.commitAsync();
                }
            }

        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("记录错误的信息："+e);
        }finally {
            //同步提交
            consumer.commitSync();
        }

    }

}